Alexander Duyck
ffed21bcee
This patch makes it so that we don't need to bother with clearing the memory out for the descriptor rings. The general idea is to only free buffers associated with buffers in use which are located between the next_to_clean and next_to_use or next_to_alloc values. Everything outside of those regions can be safely ignored since they should have no buffers associated with them. The advantage to doing things this way is that is should speed up bring-up and tear-down of the rings. Specifically we can avoid the 512 or more cycles required to memset the rings in tear-down. In the bring-up phase we then clear the memory as a part of initialization. The general idea is that the clearing in initialization can act as a prefetch of sorts for the buffer info structures so they are in the local CPU when we go to populate them. This should help to improve overall time needed to perform a suspend/resume. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.